Band clamp



United States Patent Y 2,864,149' BAND CLAMP George A. SeaverNorthridgevand 'Clarence Christophersenvandw Alexanderv P," VBartnsch, LosAngeles, Calif., assignors to Aeroquip Corporation, Jackson, Mich., acorporation of Michigan Application January 6, 1958, Serial No. 707,162r

6 Claims. (Cl. 24-280) This invention relates to band clamps" of the`general type disclosed in United States Letters Patent 2,466,755 issuedApril 12, 1949, the clamp having one end of a thin metal band secured onthe end of a screw which is threaded into a nut in al frame and theother end of the band is anchored to the frame by folding it back alonga surface of the frame, the arrangement being such that when the screwis turned to move said one end of theV band in a direction to' tightenthe band, said one end presses the folded back portion of thel other endVof the band against said surface on the frame to restrain it fromslipping.

Clamps of that general type are manufactured and sold in largequantities, and accordingly, it is desired they may be designed andadapted to be manufactured by mass production machines with little, ifany, hand labor being required, thus to substantially reduce the cost oftheclamp. v l

In the band clamps of the aforesaid letters patent, the nut in theband-securing frame has trunnions on it which are pivoted in holesformed in the side walls of the frame. The axis of the trunnions isdisposed above the axis of the screw whereby tightening of the bandcauses the band anchoring end of the screw to press down upon the foldedback portion of the band. In the manufacture of clamps having suchtrunnion construction the nut, not being a staple article of commerce,requires special manufacture, the side walls of the frame must be spreadand then bent back to receive the trunnions, and because of the requiredbending operation the side walls of the frame may not be made as rigidas is desired for optimum operational characteristics and long life ofthe clamp.

It is a general object of this invention to provide a band clamp of thegeneral type referred to above and of such structural characteristicsthat the samev is relatively simple to manufacture and avoids the abovementioned disadvantage-s.

Further objects and advantages of this invention will appear during thecourse of the following part of this specification wherein the detailsof construction and mode of operation of a preferred embodiment aredescribed with reference to the accompanying drawing in which:

Fig. 1 is a plan view of a clamp of this invention shown tightenedaround a hose;

Fig. 2 is a side elevation of the clamp;

Fig. 3 is a longitudinal vertical section through the clamp taken online 3-3 of Fig. l; Y I

Fig. 4 is a section through the frame of the clamp taken on line 4-4 ofFig. 3; and

Fig. 5 is a section through the clamp taken on line 5 5 of Fig` 4.

Referring to the drawing in detail, the illustrated embodiment of theclamp of this invention is designated generally by reference numeral410. It comprises a thin band 11 and a clamping' mechanism 12 fortightening the band around an object such as a hose 13. The clamp-2,864,149 Patented Dec. 16, 1958 2 ing mechanism comprises a frame 14, anut 15 and a screw 16. Y

The illustrated frame has a bottom wall 19, and an yend wall 20 and twoside walls21 and 22 standing up- `fright from the bottom wall. The frameis open at the end 23 thereof opposite the end wall 20.

The bottom 'wall of the frame is preferably arcuate at least in the heelportion 25 thereof, i. e. the left hand portion in the drawing, thus toprovide for engagement with the band along a larger area of contact thanwould be the case, vforexample, with a bottom wall disposed in a plane.

There is a transversely extending slot 26 formed in the bottom wall ofthe frame for receiving the ends of the band which are passed throughthe slot for engagement in the frame as will be described more fullyhereinafter. The slot is disposed substantially midway between the twoends of the band, i. e. the heel end 25 and the open end 23. As bestappears in Fig. 1, the ends 27 and 28 of the slot are made slightlywider than the stem or main portion of the slot in the bottom wall. Theslot is made long enough so that the end portions 27 and 28 thereof willbe disposed substantially in the side walls 21 and 22 respectively. Theends and side edges of the slot thus dene a rearwardly extending lip 30and a forwardly extending lip 31. As appears best in Fig. 1 of thedrawing, that edge of the lip 30 which defines one side of the slot 26is designated by numeral 32 and it is slightly convex in outline therebyto produce a sharp bend in the band where it is folded over the edge 32and secure the anchored end of the band in the frame against slippage.

The frame is especially well adapted to be `formed as by drawingoperations from a flat sheet of metal. In a rst drawing step the sidewalls and end wall may be drawn to stand upright from the bottom wall.The drawing dies used for such rst drawing step may be of suchconfiguration that the above mentioned curvature for the bottom wallwill be formed during the drawing operation. A subsequent drawing stepmay then be performed to bend the upper margin of the end wall 20 overas an ear 33 and to round olf the corners or edges along which the endwall meets the bottom and side walls.

Intermediate the side walls, the bottom wall has a lug 34 struckupwardly from the lip 31. The lug 34 and the ear 33 serve to retain thenut 15 against rotation thereof in a chamber 35 defined by the end walland the rearward po-rtions of the bottom and side walls.

In the end wall 26 there is a slot 36 for accommodating the screw 16.Such slot is slightly wider than the outside diameter of the screwwhereby the screw is movable freely in the slot without engaging theside edges of the slot, The slot is slightly longer in its verticallydisposed dimension than in its width dimension to accommodate upward anddownward movement of the screw in lthe slot as will be explained morefully hereinafter.

The screw has a finger grip or handle 38 on the outer end thereof bywhich the screw may be turned to tighten the band in the frame. Theinner end portion of the screw is made of smaller diameter than theremaining threaded portion thereof, thus to dene a pin 39 for receivingan anchor member or plate 4t). Such anchor plate serves to secure oneend (movable or moving end 41) of the band, to the screw as by wrappingthe end 41 of the band around the plate 40. The end portion 41 of theband has two holes 43 formed therein. These holes are so disposed thatwhen the band is Vbentpwardly along the vouter face of the plate 40 andover the top edge of the plate anddownwardly along the inner face of theplate, the holes 43 in the band will be aligned with a hole'44 in theplate whereby the band and the anchor plate may be positioned on the pin39 by passing the pin through the aligned holes 43 and 44. The plate 40is freely rotatable on the pin, and to prevent removal of the plate40'from the pin,the outer end 46 of the pin may be peened as shown inthe drawing. p Y l Reference numeral 48 designates the upper edges ofthe side walls of the frame. Each such upper edge cornprises a portion49 which slants downwardly toward the edge of the bottom wall disposedin the open end 23 of the frame. Disposed` rearwardly of the slantportion is a straight portion 50 substantially parallel to the bottomwall, the meeting ends of the portions 49 and 50 being rounded off toprovide a smooth edge to serve as a cam surface. The anchor plate 40 hastwo ears 52 projecting outwardly from the side edges thereof and theseextend over respective cam edges 48 of the side walls of the frame. Whenthe screw is rotated to move the plate 40 in a direction toward the endwall 20, the j ears 52 engage the cam portion 50 and thus prevent theplate from becoming engaged in the slot 26. The downwardly slopedportions 49 of the cam surfaces permit the anchor plate to movedownwardly in a direction toward the bottom wall for pressing theanchored end 54 of the band against the upper surface of the bottomwall.

As thus far described it will be observed that the screw may be turnedto move the plate carrying the movable end of the band in a directiontoward the nut 15. From the plate 40 the band extends through the slot26. The band may be wrapped around the hose 13, and the free end 54 ofthe band passed through the slot and bent over the lip 30 of the frameto extend through the open end of the frame and under the movable endportion 41 of the band. By then turning the screw in a direction toadvance the screw in the nut 15, the plate 40 with the end 41 of theband xed to it will move in a direction toward the open end of the framethereby tightening the band around the hose. It is intended thatmovement of the plate over the end portion 54 of the band will press theend portion 54 against the bottom wall of the frame thus to anchor theend portion 54 in the frame. However, inasmuch as the nut 15 is looselycontained in the frame, were it not that the nut is adapted to inclineforwardly in the frame as provided by this invention, the movable end ofthe band would not press the end portion 54 of the band downwardlyagainst the bottom wall of the frame with sufficient force to anchor theband end portion 54 in the frame.

According to this invention the nut 15 by a particular manner ofinterengagement with the end wall 20 causes the plate 40 and band endportion 41 to press the end portion 54 of the band downwardly againstthe bottom wall of the frame as the screw is advanced in the frame, thusto anchor the end 54 of the band in the frame and to tighten the bandaround the object encircled by the band. To this end the inside surfaceof the end wall 20 has a transversely extending ridge 56 formed therein.This ridge is spaced downwardly from the inside face of the lip 33 by adistance which is less than that dimension of the nut 15 from the upperedge of the nut to its axis, e. g. for a staple nut, said distance isless than one half of the perpendicular diameter thereof. Thus, when thenut abuts the inside surface of the lip 33 as shown in the drawing, theridge 56 will engage the nut along a transverse line above the axis ofthe hole in the nut through which the screw 16 extends. Statedotherwise, the nut bears against the ridge acting as a fulcrum along aline off-center of the nut and above the axis of the nut to tilt the nutin a direction of its top edge toward the open end of the frame therebycausing the screw to ineline downwardly toward the bottom wall of theframe. Thus the anchor plate 40 and movable end portion 41 of the bandwill bear downwardly against the end portion 54 of the band to anchorthe end 54 against the bottom wall of the frame.

In the illustrated embodiment the ridge 56 is formed as by the use of adie which presses a groove 57 in the outer surface of the end wall.Accordingly this groove and its resulting inside ridge may be formed inthe above mentioned drawing operation wherein the lip 33 is bent overfrom the end wall.

While the instant invention has been shown and described herein, in whatis conceived to be the most practical and preferred embodiment, it isrecognized that departures may be made therefrom within the scope of theinvention, which is therefore not to be limited to the details disclosedherein, but is to be accorded the full scope of the claims.

What we claim is:

l. A band clamp for clamping an object and comprising: a frame having abottom wall with an upper surface, opposed side walls extending upwardlyfrom the bottom wall, an open front end and an end wall at the rearwardend of the frame and extending upwardly from the bottom wall and beingintegral with the side walls thereby to dene a chamber in the rearwardend portion of the frame, the end wall having an opening extendingtherethrough, the bottom wall having a slot formed therein extendingtransversely between the side walls; a screw having a forward end andextending through said end wall opening; a nut having an internallythreaded hole, the nut being on the screw and disposed in said chamber;means on the frame for retaining the nut in the chamber against movementof the nut forwardly in the frame, nut abutment means on the frame forlimiting upward movement of the nut in the chamber; a band forencircling said object and having two end portions extended through saidslot, one band end portion extending forwardly in the frame and againstthe upper surface of the bottom wall, the other band end portion beingconnected to the forward end of the screw, the screw being rotatablewith respect to said other end portion of the band, whereby as the screwis turned to move longitudinally forwardly in the frame, said other endportion of the band will bear downwardly and slidingly against said oneend portion of the band; and a projection extending forwardly from saidend wall and in engagement with the nut above the axis of thenut holefor inclining the nut and the screw in a direction of the forward end ofthe screw downward toward the bottom wall.

2. A band clamp according to claim l in which said end wall opening iselongate and extends centrally of the end wall and its longer dimensionis generally perpendicular to the bottom wall.

3. A band clamp according to claim l in which said means for retainingthe nut in the chamber against movement of the nut forwardly in theframe comprises a lug struck upwardly from the bottom wall adjacent saidslot.

4. A band clamp according to claim l in which said nut abutment meanscomprises an ear extending forwardly from the end wall and above saidend wall opening.

5. A band clamp according to claim 1 in which said projectionconstitutes a ridge extending transversely of the end wall and from theedges defining the end wall opening.

6. A band clamp according to claim l in which said projectionconstitutes a ridge having an apex extending into said chamber andtransversely of said end wall to provide a pivot line for engagementwith the nut, said nut abutment means comprises an ear extendingforwardly from the end wall and above the end wall opening, the diameterof the nut being greater than the distance between the ridge apex andthe inside surface of the ear.

No references cited.

